/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.hddz.comlib.ui.base.quicksearchbox;

import java.util.List;

import android.database.DataSetObserver;

/**
 * Orders corpora by importance.
 */
public interface CorpusRanker
{
	/**
	 * Gets a an ordered list of corpora.
	 * 
	 * @return The most important corpora come first in the list. Callers should
	 *         not mofify the returned list.
	 */
	List<Corpus> getRankedCorpora();

	/**
	 * Registers an observer that is called when the corpus list changes.
	 * 
	 * @param observer
	 *            gets notified when the corpus list changes.
	 */
	void registerDataSetObserver(DataSetObserver observer);

	/**
	 * Unregisters an observer that has previously been registered with
	 * {@link #registerDataSetObserver(DataSetObserver)}
	 * 
	 * @param observer
	 *            the observer to unregister.
	 */
	void unregisterDataSetObserver(DataSetObserver observer);
}
